And insanely m-i-s-u-n-d-e-r-s-t-o-o-d.

Look…

If you think “Osu!” is an all-purpose secret word that you can use with your dojo buddies while on the phone, at the mall, when doing dishes or walking your dog – you’re not only using it horribly wrong, but also promoting the kind of group-think mentality that got today’s music culture to the dreadful stage it’s at today.

That’s right.

You’re the reason Justin Bieber got big.

*shrudder*

Jokes aside, let’s get serious:

What exactly does this magical “Osu!” even mean?

Where does the term come from?

When should you use it?

Why do some people use it for everything?

Do you really need to use it?

Most importantly; what’s the #1 time when you should NEVER use it?

Check it out:

The History & Origins of “Osu!”

According to history books, the expression “Osu!” first appeared in the Officers Academy of the Imperial Japanese Navy, in the early 20th century.

This fact, combined with the fact that “Osu!” is non-existent in traditional Karate dojos of Okinawa (read more about that here), tells us two things:

The term did not originate in the birthplace of Karate (Okinawa).

It has militaristic, group-think mentality undertones.

In other words…

There is something fishy going on!

Funnily enough, many Japanese people don’t even know themselves where the expression comes from. I know because I used to live and train there.

That being said, several theories exist on its true meaning and origins.

It’s a phenomenon – even in Japan!

So…

Let me now present three of the most prevailing theories on the origins of “Osu!”.

#1: The Kyokushin Theory

The first theory comes from Japanese full-contact Kyokushin Karate.

You see, in Kyokushin it’s common wisdom that the term “Osu!” stems from a longer phrase known as “Osu no Seishin”.

Mas Oyama – founder of Kyokushin Karate

In this particular case, “Osu!” is a combination of two different kanji (Sino-Japanese characters), namely the verb ‘osu’ which means “to push”, and ‘shinobu’ which means “to endure/suffer” or “to hide”.

Put together, these two kanji form a new compound word, which can symbolize a lot of stuff, depending on who interprets it: “combat spirit”, “the importance of effort” “the necessity to overcome all obstacles by pushing them aside”, “advancing with a steady positive attitude”, “not showing suffering” and “the spirit of perseverance” are some of the commonly cited meanings of this “Osu!” version.

In other words, since Kyokushin Karate requires extreme amounts of physical conditioning and guts – this theory says that you are verbally reminding yourself to breach your comfort zone by putting your physical/mental limits to the test every time you say “Osu!”.

Pretty badass!

But, is ‘The Kyokushin Theory’ the main reason for today’s ubiquitous usage of “Osu!”?

That remains a mystery.

Let’s move on…

#2: The ‘Good Morning’ Theory

The next theory comes from Dr. Mizutani Osamu in Japan.

“Hey ya!”

Dr. Mizutani, a linguistics professor at the University of Nagoya and frequently quoted in The Japan Times as a “language expert”, talks in his work about a fascinating experiment he once conducted with a group of random people in order to observe the various ways in which subjects would return a simple morning greeting.

Put briefly, Dr. Mizutani greeted unknown people on the streets of Nagoya with the expression “Ohayo gozaimasu!” (the most polite Japanese equivalent of “Good morning!”) and noted the different responses.

The result?

Although most subjects replied in a similar manner (“Ohayo gozaimasu!”), during the course of the experiment Dr. Mizutani noticed that greetings changed as situations changed.

Joggers, for instance, involved in an athletic activity, responded with considerably rougher language than people who were just out for a stroll or walking their dog.

As a matter of fact, Dr. Mizutani found that most of the joggers responded with shorter and shorter forms of the greeting, like “Ohayossu!”, “Ohayoosu!”, “Oossu!”, or simply…

“Osu!”

So, the conclusion drawn by Mizutani was that “Osu!” is a very rough masculine expression used mainly by young men toward other men, most often while engaged in athletic activities, and that it basically means “Hey ya!” in English.

But, is Dr. Mizutani’s observation of “Osu!” the main reason for our omnipresent usage of “Osu!” in modern Karate?

That remains a mystery.

Next up…

#3: The Onegaishimasu Theory

This last theory is called ‘The Onegaishimasu Theory’.

It’s similar to the previous ‘Good Morning Theory’ in the sense that a longer (formal) Japanese expression gets shortened to a more pragmatic (but less respectful) version.

“Onegaishimasu!”

In this case, the original phrase is “Onegaishimasu”, a word that most Karate practitioners have surely heard, or perhaps even used themselves, in the dojo.

Although “Onegaishimasu” is one of the most common expressions used in Japanese everyday language, it’s actually a pretty hard-to-translate term in English, and the closest equivalents I can come up with are “Please”, “Do me the favor”, or “Grant me the pleasure”, i.e. inducing a mutual feeling of reprocity and gratitude.

So, how does “Onegaishimasu” become “Osu!”?

Well, I actually noticed this phenomenon unfold myself on several occasions when I lived in Japan: While most regular students would exclaim “Onegaishimasu” as they bowed to each other before beginning an exercise, a couple of youngsters would always gradually shorten the phrase, until, by the end of class, the only thing that could be distinguished from the intended “Onegaishimasu” was a simple “Osu!” grunt.

Needless to say, these same youngsters would regularly shorten the expression “Otsukaresamadeshita” (a traditional phrase said after you finish training/work/school) to a simple “Tsukare!”.

So…

Is this the ultimate reason for why so many Karate people use “Osu!” like crazy?

Maybe!

Now check this out:

When You Should NEVER Use “Osu!”/”Oss!”

Okay…

With the history lesson out of the way, let’s finish off with a bang.

Although the usage of “Osu!” has reached embarassing heights in modern Karate today (including some MMA and BJJ gyms), people are bound to keep using it because of its newfound meaning in martial arts circles as a handy, all-encompassing utility word.

That’s fine.

You should definitely do what you instructor says!

But…

No matter what reason or meaning you attach to the word “Osu!”, you MUST know this one thing:

Never say it to a Japanese person – unless he is younger than you, lower in rank, or wants you to say it (if you’re a woman, don’t say it at all).

You see, at the end of the day, it doesn’t matter if the term “Osu!” derives from the philosophical concept of “to endure pain and suffering” (The Kyokushin Theory), from the greeting “Ohayo gozaimasu” (The ‘Good Morning’ Theory) or from the phrase “Onegaishimasu” (The Onegaishimasu Theory): As a rough, masculine expression, “Osu!” should be used very carefully, especially toward Japanese masters and people of higher rank/status/age than you – and more so if you are a woman.

It’s fun to imitate Japanese culture (in some dojos, this seems to be what 99% of class is about), and it’s not a federal crime to use “Osu!” inappropriately. But it should be used in full understanding of its meaning and implications – and only if you feel you can stand behind it.

“But Jesse-san, what should I say instead?”

Okay.

So what should you say instead?

In 9 times out of 10, there are two very good options:

Say “Hai!”…

…or say nothing.

“Hai!” is the commonly used word in Japanese for “yes”/”understood”/”affirmative”.

That’s what we say in Okinawa – the birthplace of Karate – as well as in many other places where the “Osu!” parade hasn’t arrived yet and people value humility.

More Articles

183 Comments

Chris Mattison

March 28, 2013 at 10:19 pm

Sure, "OSU!" can be/is used as a "catch-all" phrase, but I think the bigger annoyance is the "Hai" fest!...especially when the offending martial artists/school has ZERO attachment to a Japanese school or style (aside from being "karate").Sensei: "Front kick; hai?"
Students: "hai!"
Sensei: "One"
Students: "hai!"
Sensei: "Two"
Students: "hai!"
...I'd much rather hear OSU! :-)Good read!OSU..er...goodbye :)

Glad to oblige. ;)I was visiting an independent "American Karate"-like (I think...?) school where an old friend trains...tried to keep up with a lot of "kroddy" that night; my school/style is traditional Japanese....that said, my only point of disagreement with your post is when the head-honcho (our Founder/Grandmaster, who is Japanese) says "OSU!", I respond in like. As far as I'm concerned, in the dojo, if I'm following his lead I'm doing the right thing(s). Annoyance to some? Sure, but if that's the culture of your style, then I think it's acceptable.Also, do think the word puts everyone on a level playing field, "singing from the same hymn book" if you will, without butchering a language. I guess there are trade-offs either way, which is the least of all evils? Who really knows...

Oss Jesse-san,sounds like you've never visited a "Go Kan Ryu" dojo ;-) I was flabbergasted by the amount if "Hai".... thought they breathed by the word by the time I walked out.... which was only 5 minutes.Let make an official list of "McDojo's Around the World"?Cheers mate

Hai is the ultimate expression of militaristic and subservient karate, but no-one who has ever used "osu" is in ANY position to criticise its use.At least the modern use of "hai" serves a considered psychological function, to ensure engagement and to force students to at least stay alert enough to affirm that they are not drifting off to sleep. Furthermore, the word is at least contextually correct in its usage AND that usage is understood by its practitioners. Unlike Osu.It IS sometimes definitely overused, often by control freaks, but I don't think anything is served by people looking down on other styles.

Bob

November 7, 2016 at 10:09 am

I use "hai" or "hai sensei" in the ju-jitsu (the japanese kind not the brazillian kind) dojo i train in.
However, only when sensei gives me a direct instruction in front of the junior class, as a sign of respect and to set an example of respect in front of the junior class. Otherwise we tend to just speak english and get into the training. With the exception of the word "sensei" which out of respect is still used to address, well, the sensei.

Yes, Skatch, that is true. But one thing Japanese people are weary of here in Japan, is that Osu has a mafia connotation to it. Which was associated with the male machismo, endure anything thrown at you attitude.

Jesse sensei:
I am JKA member, the Shotokan. But I do not claim to represent any official opinion of that honored karate organization.
I am surprised that you didn't have anything close to what I learned of the meaning in my early years of martial arts study when I was very curious about the meaning of Osu. That it is two words phonetically written in 26 letter alphabet to the best of my abilities without researching for this response to your thoughtful article, "Oh" and "tse," together looking more like "Osu" pronounced together. "Oh" means effort. Tse means patience. Together it means, "Please be patient with me I'm trying. I was told that karateka were required as early as the early 20th century in Japan to say, "Osu" or other acceptable greeting to higher ranking students if they saw them anywhere, and continue saying it and bowing within reason until acknowledged.
An appropriate response to a command from a sensei, for example, "Do is "Osu," translated into my operational definition as, "I'll try," instead of, "Hai" translated "I can do it," so that you're indicating effort in attempting, and knowledge that you need improvement before you can say you can do the requested technique correctly and precisely as instructed.

thank you for this comment, tho it's gone largely unnoticed in the rush to ridicule others. It's a shame when people look for ways to feel superior rather than genuinely try to understand what's going on or even respect the efforts of others to learn new things & improve themselves whether "hobbyists" or not. I rarely find mention of Shotokan, which was the training I received when I was a child. We were taught using Japanese words & ideology and given history lessons & meditation as part of the training. It was one of the most important experiences of my life in a tiny outback town in Australia. Osu was explained to us as you explained it, the whole emphasis was on respect & humility and that word was part of it. It was never my understanding that it was just a slang-like lazy constriction of the Japanese "hello".

Teaching here in Japan, I've only heard it used very rarely from teachers in public schools. And those were the teachers that came from a sports environment upon entering a class or the teacher's room.

d t brewer

February 13, 2017 at 7:44 pm

After some time in Karate I have heard that term all to often. When I was on the island (Okay Okinawa) in the early 80's there was a young Marine who had just arrived and asked me to show him some of the dojo available. He had that irrating almost knee jerk reaction to say the word (oss). So I took him to a dojo owned by a sensei you was education (all names withheld) in America, and the oss continued: To the displeasure of the Okinawan sensei. After several moments he looked at me and asked if the other student was retarded (his words not mine, Nothing else be said.

Chris. In that circumstance, the word "hai" would get annoying. That being said, it is still correct, while "osu" is not (as far as I know.) It seems similar to counting push-ups saying "One sir, two sir." -Respectfully, Dean.

Dean,I've heard the "One sir, two sir..." thing too. I don't particularly care to hear OSU! after every pushup either. But as I said in my second response to Jesse, it levels the playing field without butchering the language. I live in the southeast United States; "ichi, ni, san, sichi" is slaughtered enough, hearing "hi" 1000 times a night might make me put myself through a brick wall, lol.-CMp.s. --finding it excruciatingly hard not to sign off with "OSU!" o.O

My japanese teacher said that people started using as a sort of what's up phrase. Basically people were saying it while flicking their heads up. Like some people would do in America when they say what's up.

I think that is the same mentality as shouting the word Ki-ai. If shouting the English word doesn't make sense then why does shouting the Japanese word. To be honest, I relegate everyone I hear saying 'osu', and particularly everyone who uses it as a response on Facebook, to hobbiest status rather than budoka, but then I am a koryu snob. Nice post

Shioda Gozo (10th Dan Aikido Master) and other Yoshinkan masters use "Osu"; and some of us also say it on Facebook. We say "Osu" as a sign of acknowledgement, respect, appreciation, and perseverance. "Osu" is easy to say, and does not restrict the breathing. "Osu" keeps things simple - we don't want too much conversation during class. I think it would be wrong to relegate us to hobbyist status.Is the use or non-use of "Osu" really of such great importance to you that you would judge people based on this factor alone?I heard that "Osu" originated in the military. I don't get an overly militaristic feeling from "Osu" in our dojo, but I feel it would not be inappropriate to use martial conventions such as "Osu" in the martial arts.I will be honest too, at the risk of causing offence.I believe that "reiho" - respect and good manners - is absolutely fundamental, perhaps the single most important principle of budo.So it upsets me and boggles my mind to see highly-ranked budoka squabbling over rank or politics, or rudely disrespecting other martial arts even over the slightest differences. It seems to me that this is poor reiho. On the other hand, it's okay to have a joke and a bit of friendly banter...I hope you won't take offence, and can appreciate what I am trying to say. I probably wouldn't dare to say this to anyone in person, and especially not to a master. It's a pity, because I think it needs to be said and it needs to be heard.

Jesse-san, what a fantastic post! I truly agree with you on the hai/silence theory! I still have the sensation of being in a church while practicing Karate (just change osu with amen and you get it!). Thanks for your job!

YESS, definitely right ! Like my man Kurt Osiander always says..."now shut up and go train!" :-DHere in Austria, not only Karate Dojos uses the Phrase, even BJJ and traditional Jiu Jitsu Dojos uses the word to confirm the masters advice for example....cheers and greetings from vienna !

Good read! You can't really escape, hide or run from "Oss!" - it's almost everywhere. Even if you're not an active karate-nerd (but was in younger days and nowadays flirting with the idea of "coming home").My point is that using a non-domestic term without knowing it's cultural root and meaning is equivalent to being unrespectful to its origin. Now, since "...that remains a mystery." (even to those who live in the place of origin) the best part of this article and a very, very, very valid way to handle "oss" is"In 9 times out of 10, there are two very good options:
•Say “hai!”…
•…or say nothing."I'd even prefer the last option more. Respectful silence, possible relished with a respectful gesture like slightly nodding or taking a bow one can't be wrong.Problem is that nodding or bowing can hardly be written down :)In the latter I'd say ...with best regards,
Carsten

I just sound off with Hai/ Hai Sensei. I follow some other karate folks. When they post a picture of a Master or kitten in a GI. they get about 1000 comments of just oss...its whatever. I'll stick with hai.. I know 100% its meaning.Domo Arigato gozaimasu Jesse San

Hah! I've noticed that kittens in gi are pretty "Osu!"-worthy too, Peter-san! On a side note, adding "Sensei" after "Hai!" is not the norm - although I know that a lot of Westerners do it (probably because they think it corresponds to "Yes, sir!"). I actually saw a master in Okinawa trying to teach some Mexican dude that he needs to drop the "Sensei" part when they speak. Aaah, cultural differences -what would life be without them? =)

Yes, Its very interesting how much difference there can be within Traditional Karate, Okinawan Karate, Specific Styles, even within an organization from school to school. They way I look at it. Don't sweat the small stuff... (not saying do ask or stride to be better) but don't judge a group or student for small details... Just train. Karate is (for me) is not how I compare to other's skill or technique but, how a stack up against myself 1 year ago. If I'm the same (or worse) I need to step it up some. Masakatsu Agatsu

I find it amusing how people also misuse the word gi (clothing). I have rarely heard the proper use. I train in kuk sool hapkido and people a) cannot pronounce the uniform name properly and b) do not know that a generic word for cloth is "bo(e)k (this is the same as "gi"). To use the terms correctly, prefixes are made: to(e)bok, hanbok, kyobok, etc. The same as gi: karategi, judogi, aikidogi, jujustugi, etc. Gi and bok are not used alone.

To be honest, the first time I heard "Osu" was at nationals 2 weeks ago, some competitors said it as we were bowing in before the competition. My dojo and most other dojos I've been to have all said "hai". But maybe its just this island that no one says it. I enjoyed this article...even though I wasn't exactly sure what it was about :P Thanks Jesse!

Maybe "Osu" is a contextual word that dojos have adopted and the meaning is understood in that dojo. If it has become the all purpose word so be it. If we are going to follow the ,"unless it is done in Okinawa" approach then a lot of what we do in the dojo would go. If thats your flavour, so be it. Osu in our dojo helps build the spirit through a collective understanding more than a simple "yes" could. It works for us. If it doesn't work for you, that doesn't make it inappropriate. I enjoy your articles but you do put Karate to often in the us (we are right) and them (mcdojos) categories too often. I find it is never that easy.

Agreed. Language is a fluent thing, words are adopted from other languages and can change meaning. In Holland karatekas and kickboxers, recreational and world-class alike, use 'Osu' as a term of respect, good sportsmanship and a healthy and fair fighting spirit. I have never heard it overused, and I like both hearing and saying it.The one practical thing I take away from this otherwise interesting article is not to use the term with japanese people. The overall message to never use 'Osu' seems, as well as the usage of the term McDojo seems, well, a litlle snobby and disrespectfull to me.

I like your reply Stuart. I use the analogy of the English Language. As an Australian, we have adopted, changed, vulgerised and destroyed the Queens English. Does that make it not relevant in the context of our identity. As with the spread of Karate outside of Okinawa so will interpretation and meaning behind the words change. If there is a context for it (regardless of origin) then not sure why it is an issue. Like anything understanding the origin is important but so is recognising the change and adaptation.

Love this article Jesse-san! Gives us a little more understanding on this enigmatic OSS-ing concept.I've recently heard "OSS" as a kiai! No way! Too much! It usually goes hand in hand with the 20+ kiai katas .... No comment!Multiples merci encore Jesse!

Thank you Jesse! Sensei Ron Lindsey has been saying for years that he never heard the word " Osu" when he was training on Okinawa, and never heard any Okinawan Sensei use it. Sensei Osborne told me the same thing. Thanks for posting this!

Hello JesseThis is a great article on the use of Ossu. I read a similar article of the word Ossu in Black Belt magazine a few years back but it was no where as good and left me a lot more confused at the time.I am now living and training in Japan and from my experience I would say the good morning theory is the one that holds the most water. Baseball players in particular use this greeting at all times of the day but most often in the mornings.I am a little more weary of the Kyokushin theory as many Kyokushin Karate-ka would tell you Mas Oyama invented Karate, or at least the best Karate if you would listen to them. However Oyama may have repurosed this rough greeting to fit the atmosphere he wanted in his Dojos,I have trained in both Kyokushin and Seidokai Dojos in Japan and the word Ossu is as all purpose as it was in my Shotokan Dojo in Canada. Lets remember Oyama did train in Shotokan for some time as well as several other styles of Karate before founding Kyokushin.You give a great warning at the end, be careful with the word especially when in Japan. Spewing the word Ossu makes you sound a bit rough especially in a culture obsessed with pleasantries (this I one of my favorite things about Japan). Now if you are into knock down Karate perhaps that is your intention but as you said be aware of your surroundings and do what makes sense. From my experience there is no place for the word Ossu in Aikido or Judo the word Hai is more often called out.Any ways that is my two cents keep up the good work.

Our school only uses Osu on Gasku and only then when there are no non-karate-ka ladies present. We follow the train of thought that it is a bit offensive and not used in polite company/normal conversation. it is banned in the dojo normally, it does creep in a bit after constant use on gashku.Our general knowledge on the history of Osu is that it came out of the Japanese Military Academies pre and during WW2. Macho, aggressive and combative!

We only ever use it on gasku or our intensive training weekend when there are no non-karate-ka ladies around. It is only used in those timeframes and is frowned upon in the dojo normally.We are taught it comes from the Japanese Military Academies before and during WW2 and is very aggressive, martial and macho. Not suitable for 'polite company'.But that's just our way!Matt

Yet another great post. Thanks Jesse!
I practice Itosu-ryu and we never use osu inside the dojo. We do use it when we enter and exit though. Which I after this post, need to bring up with our Sensei. That just seem weird.

Thank you for clearification. At my old dojo we used "Osu" for everything: "kiai," greeting, acknowledgement, bowing, and so on. Now that I'm in Isshin Ryu, I'm having to learn how to drop it and start using "hai." Either way, I'm passing this article to old class mates who are still at my old dojo.

I did change from "osu" to "hai" in my dojo 2 years ago.
students sometime still use it especially those who use to practice also in selection but in general, the change was easy.
Just have to explain it means nothing for japanese and things goes very fast.Great article!

Wonderful article and very useful information.
Our feelings are when in Rome do as the Romans do.
So if its being used to follow the use. When your not sure silence is always golden
The masculine part is more of a concern as to share in the macho activity. Real men use osu/osss.
OPps... let's not go there...
How about a discussion on god bless you for a sneeze?
Love your point of view.

This is a great post. I truly believe in theory #1, but while in Japan a friend of mine bought a book. I can't remember the exact title, but it was something like "Top Japanese Dirty Slang Words". Guess what the very first word was? "OSU!"They defined it as meaning "Wassup?" or "What's Up?". The answer you would give would be "Wassup?" back.OSU?OSU!

Thanks for sharing your thoughts about the "Oss" thing...I never use it in letters UNLESS I receive letters from HQ in Japan where they use "Oss"...In my dojo?? yes, but not very much...in fact I am not that keen on the traditions behind Karate Do...only the traditions that I feel nessesary to keep up the "politeness".I am more annoyed by the "San"-thing...we are WESTERNERS and not Japanese... ;-)Rgds
Ole

Jesse: I think the use of "Oss" in the world of karate is more style specific than people realize. It is very prevalent especially in the Shotokan style. My theory is that because the Shotokan system concentrated on getting karate in the universities and the college programs were pretty rough and tumble, their karateka gravitated towards the use of "Oss". My bet is that Funakoshi probably never used it but when his system spread to Japan, that's when the "Oss" word spread also. It did not come from the Okinawans. I have studied a Japanese style for over 40 years and have never heard "Oss" used at any of the our style's dojos in Japan.
'

Hi Jesse-san, I am -so- glad somebody with a wide following has had the guts to address the “osu issue”. I’ve created a quick test people can take to see if they should use the term “osu”:a) Do you study a Japanese style of karate (rather than an Okinawan style of karate)?b) Do you want to be seen as behaving like a rude, vulgar, and generally immature thug?If you answered “yes” to both of those questions, then you should you should definitely use the term “osu”.

So, are you saying that as an American woman training at an American dojo, when I use the term in class, I'm using what amounts to Japanese bro-slang that wouldn't be uttered by a proper woman in polite Japanese society? I find that highly amusing, kinda makes me want to say it more, purely for entertainment value. (We basically only use it here upon bowing at the start and end of class, as a respectful acknowledgement of willingness. I've never seen the degree of "oss-ing" you mention.)

Aubin, the best comparison I've heard is that "osu" is basically the Japanese equivalent of "football locker room" speech.Or really any similar setting where spitting, swearing, and jokes about genital size are the norm.

Hi Jesse, Somewhat confused about the 'when not to use' part, having trained in various styles and forms over 23 years, and currently in shotokan, I've seen Japanese seniors of both men and women using this phrase fairly commonly, although always in a karate context and not outside the dojo. True I think western culture has taken it a bit far in the usage, often an instructor might describe a technique, and ask Osu? before everyone chimes in Osu! in understanding, etc. If it was 'THAT' bad wouldn't a senior instructor from a style, ANY style, say something about not using it? I mean, they go on forever about what not to do on stances, punches, kicks, other forms of dojo etiquette, surely if it was as bad as you are trying to make out in this article someone from some style somewhere in Japan would say 'Hey guys, don't go around abusing this phrase Osu because it's bad mojo' or something?' But noone has said anything. Ever. Nada. What gives??

Jesse-san, great article. Now I can pass out a copy of this article rather than argue with my Shotokan, Kyukushinkai, Japanese based karate-ka friends. Yes, Jesse despite all that you heard I do have friends.Chinen Sensei did not use the term "OSU" in his classes and at times when outside visitors from other styles would visit the training session. His explanation was always towards the Naval Officers view. His Dad was a WWII Naval Submarine Officer that rather than surrender at the end of the war they road the sub to the bottom and scuttled it, in turn killing everyone on board.His explanation was akin to US Navy officers moving through a crowded below deck hallway where sailors would place their backs to the wall and allow the Officer by. Rather than returning a dozen salutes the Officer would say "Carry on" or "As you were".The use in the Japanese Subs were due to cramped quarters and officers were constantly rubbing shoulders with enlisted so the use of OSU which is a contraction showing seniority of the officer to the others.OSU KANJIDuring the build up of WWII many of those officers trained in various arts such as Judo, Shotokan, etc. that used the term at their colleges clubs. Please note that the older Ju Jutsu arts e.g. Daito Ryu or Sword Arts do not use this term.

Ahem.....as I was saying. I went to train this morning for the first time at his Goju dojo where we are spending our Spring Break. What I noticed, right off, were the use of traditional greetings and thank yous, etc. But then I had to really tune into the use of "Hai Sensei" after each and every instruction. It really didn't bother me....I just had to switch over because we use Osu in our school. Not quite as much though. For me, I think that when we train in our own school, we do as the Sensei directs. And when we train in someone else's school, we do what they do. Being in the US, this does not create the kind of problems it might in Okinawa. One of the reasons that I use Osu in my classes, is that we are connected to a high school and the majority of my students are 14 - 18 years old. I would much rather hear a student acknowledge my comment or instruction with "Osu" instead of "Sure" or "Yea." Another great article and more to think about....but more importantly, an explanation for my students of where Osu came from!!!! Alofas!!!

great post. I had heard that it was an imperial military greeting like the US marines using the Hooah to each other which would bring the osu as a combintation of both 1&2. On a funny note, I heard someone try to use Osu as a yes at a Japanese restaurant once

Great effort, Jesse!For me, it really always comes down to the sincerity and spirit of the term's usage. The intent, what feeling and message was behind the words, is often more important than the words themselves. But we are complicated beings, aren't we? OSU!

That is by far the most thorough explanation of "Osu" I have had the pleasure of reading. I was taught, as you mentioned, Osu has many meanings. However, in our traditional Japanese Karate style, Osu is most often used to convey the "keep pushing" meaning. In other words, it is used to encourage the student not to quit on themselves.Osu!

OSU! Some words transcend their original meanings and become martial arts school specific; in the Phoenix Way school, based on Kyokushin, the simple word represents the philosophy of the Association. Without it, and the understanding of its meaning to push on and constantly seeking human depth, our training would lack true budo purpose.Good piece and debate. My best. OSUDan Soller

When I was a kid in the dojo I attended the tradition was to say "hai" for "yes teacher" or to say "I got it"" as a reply to the question "wakarimasu ka", I mean in case one actually did understand the explanation. Well, if you wanted to be very formal "wakamrimasu" and "wakarimasen" was OK to be used too, but I never did, it was more like a thing that the "diehard fans of the movie Shogun used. So that "hi" kinda stuck with me to this day, it might be just as wrong as saying osu, but it is an easy way to get over with the talking and continue with the doing. So I just use hai. Except when I talk to an echte Japanese instructor, to them I say "yes sir". They seem to like more a native polite version than a half assed Japanese.

Theory 4, It is an international word that is nearest to the natural sound a gentleman makes when you kick him in the balls and he doesn't want to cry in front of you.It also works when you have been punched in the solar plexis and it is about the only word you can manage to say as you try to re inflate your lungs, like your key word in transcendental meditation.I suppose shiiiiiiittttt!!!!!! would also work......

BJJ community too uses the phrase oss. even here in finland. it started about a year ago when a guy name bernardo visited our gym. hes from brazil and is a word champ at blackbelt category and a belongs to the top of our sport. I asked him about this oss thing. He told me that it started as a joke but now every body uses it. Why? because of a mma tv-series aired in brazil. The host of the show began every single episode by saying oss. Bernardo told it was a funny thing and soon it became a phenom. It spread via twitter and facebook rapidly. Everybody was posting pictures and commented by saying oss etc. I dont mind saying oss among bjjcommunity because the meaning is different. but wouldnt say that to other communities for example such as karate guys.
Maybe this was helpfull?
-Tuomas

Jessie, thanks for the great article. The writing was witty and spot on. I was raised in a traditional Japanese Dojo where the "word which will not be spoken" was never ever used. I knew it existed but it had never entered my ears other than an occasional 80's B rated Karate flick.Really enjoyed the read. Domo arigato gozaimasu.

I did some karate about 30 years ago and returned to it about 18 months ago when my son wanted to try it. On returning after such a long gap, there are a few things that I did not recognize and "Oss" was one of them. I do not remember it at all from 30 years ago. We used to just say "Yes" or "Yes Sensi". Does anyone know if this is because "oss" is a more recent thing or is it may fading memory that is at fault?My view is that I do not speak Japanese so I do not say "Oss". Yes, I use the Japanese names for techniques but then I use the Italian name for spaghetti because there isn't an English word for it and the English translations of karate techniques are so clunky that the Japanese is much easier.

I think that whatever country you live and train in, use that language. There are millions of Japanese language speakers that can't kick, punch or strike, but they can speak Japanese very well. The same with Chinese, Korean, etc. There is too much language misuse and unnecessary mysticism associated with the languages. IMHO.

._____.
And all that time I thought Osu means OK/Yes sir/alright ! >_<
We don't use it a lot in the dojo where I practice,but when we do,we use it when our sensei asks us to do something and we agree polity as in "Yes sir" .
Should I explain it to my sensei or is it ok if we keep using it like that ?

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Hi Jesse,
Thanks very much for this article. I started googling for OSS usage one a acquaintance of mine told me that I was using OSS wrongly. I guess I was not too wrong from what I understand now (but he wasn't wrong either ;-)Above you wrote Never say it to a Japanese person – unless he is younger than you, or wants you to say it (and when it comes to women, don’t say it at all.) So can I assume that you mean Japanese women?Thomas

Words only mean what they mean in that context. Around our dojo and crowd, OSU means hello and "I'm one of you" or " you are one of us".Thanks for telling us about what this word means elsewhere. Of course, they'd probably not even recognize the word the way we pronounce it.In fact, I once posted asking about the origin of such terms:
http://www.bbat50.com/2009/10/words-we-useour-gangwords.html

I'm from Germany so I used OSS as this is the common spelling here (and it's pronounced more like Ous as you mentioned somewhere else). I (and probably most people in out dojo) used it the way like in the theories described above (#1 "Yes, Sir (sensei)!", #2 Hi (meant as a polite greeting), #3 Respect when starting a training with a partner). What I was not aware is the fact that it looks like all these terms sound the same but have a different origin.Anyhow, I'd like to know whether Jesse's "don't use it with women" aims to women in general or Japanese women.

Great article. Though I dont pracrice Karate, I do practice kendo here in Japan.I think the Ohayougozaimasu theory is a big one. Most verbs and sentences end in a masu or desu sound that comes out as an elongated s.I've practiced at a lot of japanese dojo and university clubs and I usually only here people say osu, or asu, 'su in the university dojo. Some adult males use it but only with their old buddies. And never women.The students take something like arigatougozaimasu and make it asu or azas, and Otsukare sama deshita becomes otsukare'suSince I practice a lot, I once made the mistake of replying to a female friend of mine with osu instead of onegaeshimasu, it's like saying yeh instead of certainly miss.So I think folks should be mindful that the word they are saying has an unclear origin, as well as a possible meaning in japanes, a language with a lot of layers.

I don't believe that people should be responsible for the hidden historical overtones of a word. Example:"Goodbye" - I believe that it derived from "God be with you." This is the historical hidden implication of the word. As an atheist, should I avoid the term and take umbrage when my well-meaning friends mark by departure with a well-intentioned: "Goodbye"? I don't think so.But, as a contrasting example which illustrates another point. There are terms in our language which convey current significant biases and these should be avoided at all costs. For instance, "boy" used the wrong way. And terms like, "run like a girl" or you "hit like a girl." BTW, I love the way this has become a bumper sticker using irony to make a point. The best clarification of the put-down inherent in the term is: https://www.youtube.com/watch?v=XjJQBjWYDTs
(if yo haven't seen it, watch it).Jesse, Thanks for the incredibly well researched historical and cultural insight into the term and of course, in some places in the world, be careful of its use. But for those of us who have enormously enjoyed and benefited from training in American karate schools, derivative of foreign martial art schools, I don't think we need to shoulder any social responsibility for minor affectation of using a few foreign terms.I would like, as long as some of you are willing to engage in a nerdy discussion of the implications of language and hidden overtones, like to raise the question of throwing around the word "McDojo."I mean, in a discussion on the implications of language, seriously? Aren't you being a lot more overtly "judgy" in the use of that term than the innocuous "Osu"?Respectfully but with perhaps my tongue in cheek,
John - http://www.bbat50.com/2009/10/words-we-useour-gangwords.html

Great article....I became tired of this term many years ago, and have remained silent since. It is a crude attempt of instructors and students to sound "Japanese" I guess. Kind of goes along with calling people "hanshi, shihan, kyoshi", etc, but that is another topic....

Well, to each his own. Whatever your school promotes, your Sensei wants you to say, or you feel compelled to say as a form of true thanks or appreciation is just about o.k. with me. Like anything, many practitioners have diverted from traditional arts and words into a more current Westernized version. I can think of a lot worse things to say than "OSU!" Karate in some ways has also transformed in our culture, yet even in its transformation still provides a great benefit in our modern world. Thanks for the research. I absolutely always learn something great here!

I already made my comment on this one elsewhere, but am itching to comment again. People still seem to not understand the meaning of OSU. Let's ask some questions here, "Who's to say that it is right or wrong to use it?", "Who's to say that I should use a yoga mat or chant OM when practicing yoga" or "Who's to say that I should be driving a car to work instead of walking??" OSU is mainly a part of Kyokushin and Shotokan community. As a matter a fact it is a part of official IKO dojo etiquette. Obviously Masutatsu Oyama made it official and his followers continue the tradition. Is someone here saying that Kyokushin or Shotokan karate is a Mcdojo art? I sure hope not. Thanks to Funakoshi Gichin and later other masters from Okinawa, we now can enjoy the "Modern Karate" as we know it, perhaps watered down a little bit, but nevertheless a beautiful art. Let's NOT forget the true meaning and essence of "Budo" which is "Perfection of character of it's participants" We fight against one enemy - "our self"(and Mcdojos :-)of course) and OSU is a good reminder of it. The meaning of OSU is "Oshi Shinobu" (Endure under pressure) so as long as it is correctly understood, there is nothing wrong with using it. It is a reminder to oneself to push through and never give up. It has a very deep meaning to those who understand it. Let's not disrespect here those karatekas who's OSU is a part of their style's (school) tradition. There's a time and place for everything. But of course OSU as anything else for that matter is being misunderstood and widely abused, especially by Mcdojos and Martial Art's wannabies. I've been a practitioner of Kyoukushin, Shotokan and IAIDO for past 34 years and just recently opened my own dojo. I constantly remind and educate my students about it's meaning.
I will though refrain from commenting on HAI, HAI, HAI, HAI. this one deserves a special place....... right next to Mcdojo logo.
Rob T

(I know this comment is 3 years old, but I just came onto this page today and read it - and I'm sure many others will be recent and future readers too, so I'm going to go ahead and reply anyway.)You do realize that actual Japanese people use "Hai" all the time. It's part of their language, like "OK" or "Alright" is in English. It's the most natural, and actually quite respectful. On the contrary, "Osu" is highly irregular in regular polite Japanese conversation. As a native Japanese speaker, I never use it. (Also because I'm a woman.) It just doesn't make sense if I use it. I'll explain more in detail below.Keeping it strictly in the dojo is fine, but outside of the dojo, it's not something to just throw around. You might as well be calling everyone you meet on the street and your boss and a client a "bro" and going, "Heyyyy...wassup, bro, yo??!?" which would certainly get you strange looks from people.To keep things in context, take this example: Just because the Insane Clown Posse and their followers(Juggalos) go "Whoop Whoooop!!!!" as a common greeting and exclamation to each other, do you think Juggalos AND Americans would appreciate if foreigners misunderstand this Juggalo culture and start thinking it's right to go around saying that to everybody on the street? Hey, it's still in English, and an American band totally said it's right. But then be prepared to get a lot of strange looks if you just randomly start saying "Whoop Whooop!" to people.

I began training in the Goshin Do system in the mid 60's in NJ, and don't recall hearing anyone use the term OSU until the 80's. Not sure why it took so long to enter into the conversation. What I did notice was that the term was mainly used by senior dans when greeting their juniors

After uttering the sacred word "OSU", for a number of years, I decided that because of how we over used it, I would just stop saying it until such time as I felt it could be reintroduced into my dojo conversations.
It is now more than 30 years since I last used the sacred word and still counting. Maybe someday, when the time is right, I will again say "OSU".

I agree and tend to use hai as a response (never as a kiai). My Shotokan Sensei (i do Shotokan and Shito-Ryu) is a fan of osu and will respond sparingly to appease him but also use mostly hai in his dojo as well. I have been fortunate to attend some of Fumio Demera's workshops in the past. Due to his health issues he did a speaking seminar for us last time about the benefits of karate. He got onto the topic of osu and said in nice words that the use of it was rather low brow. There is definitely a rough element of Japanese practitioners who use the word. He said that the use of hai was 'classier'. That sort of substantiated what I thought to be the reason for hai being used in some of the dojo's in Japan. I admit to being probably a pain to my Sensei's though as I always ask about these things and don't like to do things blindly without knowing what the reason is for it.

Excellent explanations. My primary dojo say Osu a bit (ie after the rei's - except to shomen and sometimes to indicate "I understand" / "Understand?". I tend to prefer nodding (especially if I have a mouth guard in). The other dojo (affiliated but Shito ryu not goju ryu) use it ALL THE TIME for EVERYTHING.....partly it increases the kime (spirit - hope I remembered the right word) but partly it just does my head in.....I hope they don't mind that I just prefer to be the shut up and train variety of person.I like the Osu which means Push through against all adversity - what our sensei teaches (or my version which is train hard 110 % no matter what / no excuses) which makes sense. I don't feel offended though if he or the other sensei signs on or off on an email / text with it as it's kind of like a reminder of what I should be doing :).

Osu. Thank You! I came looking for this and got what I needed. But I will still say Osu! Coming from a Kyokushin school with 17 years of training and a Nidan, I will say that "Osu" first is a sign of respect. We bow onto the mat (tatami) and we bow to the Shihan or Sensei. We use it to show respect to our Masters and Elders. I got to say it to Shihan Al Rivera, Professor James Powers, Professor Vee, Professor Ronald Duncan, Professor Moses Powell, Professor David James, Master Lew Neglia, Grand Master Arron Banks. Yes, we do mean "I understand", and "Do you understand". But first is respect.

I wonder why it is so important for Americans and non Japanese to use " OSU ? It is a senseless term that really has no meaning, other than the meanings applied to it by overly conditioned karate students and instructors. I mean really? Does it make us feel like we belong to an exclusive club or fraternity? Why not use terms that are actually from a dictionary ? I am not criticizing those who use it...just suggesting that it has been way over used.

Hello to all Karate nerds an Jesse-san
Great article.... I've never been taught about the meaning of OSS/OSU/OSSU....And I think that this lesson should be one of the first to be taught in a dojo, otherwise we'll never be able to improve the future karate-kas (and that is our duty as karate nerds)I've always answered my Sensei with Oss.. even if it is to show him that I understood and that I'm ready to do the kata, kihon, etcetera... But now I see that is a lot of different meanings and the best choice is to (for sure) do what your Sensei expects (meaning respect) but knowing that this is not the best answer... in other words as the karate nerd guide says.... think outside the box....

So, we're still on the old OSS topic? Here is my third contribution to this conversation: Many years ago, a Japanese Judoka who had visited the karate class I was teaching. After observing our use of the word or term OSS, he informed me that this was not considered polite in mainstream Japan , and that it was never considered a word, and he mentioned that it was a method of response among the military of Japan during war years between soldiers or navy men and their commanding officers.

Jim, the article from Jesse clearly states this as ONE of the possible interpretations, the "Yes, Sir!". In that respect it's one valid use to bow against your sensei telling him that you understood and will give your best. Not much different to what the full-contacters express their kick-ass attitude ;-)

I've only used this term when first greeting a martial artist whose spirit I respect, usually with a small head nod. Recently, I listened to an instruction on youtube and it was used as a catch-all (are you with me, boys?). In our style (Hapkido) any noises are made as an exercise of ki(Qi). Many schools today yell hai, but they're only using their voice box. In a true practitioner you can hear the (G)utterance of ki. Said in the company of recognized practitioners, it is both a proclamation and recognition of shared respect.

quote: Never say it to a Japanese person – unless he is younger than you, or wants you to say it (and when it comes to women, don’t say it at all.)“Osu!” should be used very carefully, especially toward Japanese and people of higher rank/status/age than you – and more so if you are a woman.---- I appreciate your article and should probably not even post, as one who sort of knows how to use Osu...the whole mention of rank and status....you are certainly not saying that foreigners are of less status than Japanese and especially of Japanese women?I didn't think so. Rank applies within an organization.
Status applies within the mind.There are ways to say that a well-spoken person should be conscious of the effect of their words, without descending into a pecking order mentality.To say it sounds a bit rough and martial for the family room is probably enough.to give you credit you did cover yourself by saying it doesn't really matter.but just felt that age and rank and status doesn't really decide whether one should speak respectfully to others or not.but yes, if you go around saying Osu at strange moments, it can be sort of like snapping to attention and saying, yes sir!project mayhem anybody?

Actually there is nothing wrong with using ossu, in the culture (martial arts, especially) where it is the norm.As an analogy, people might stand up and shout various things at a football match which would be inappropriate at a ballet. Ossu is fine, in Karate and Judo and Yoshinkan Aikido dojos. A masonic handshake might be lost on a girl scout.Personally, I'm 30 years in Japan, and in three martial arts. In one, Ossu is encouraged in our dojo, like a secret code. In another, Ossu is never used but I do ... occasionally ... use it to my shihan and he seems to like it, I think for him it harkens back to a time.But (and this post is in reply to JayRay), it isn't a universal greeting as much as it is a statement of affirmation. It passes for a greeting in some dojo cultures but more polite would be to say, if off the mat, "Hello, sensei" or if in the morning, "ohayogozaimasu sensei" or first time on the mat, "yoroshiku onegaishimasu sensei".These are greetings.On the other hand when being corrected or instructed, especially in martial arts, ossu is appropriate, unless you are at a dojo where nobody ever says it, ever, and even then it is probably fine. ;)If you don't speak any other Japanese, however, perhaps "thank you, sensei" would sound more natural.The non-martial way to say "yes", "understood" would be "hai".However, please know that in some situations, in some teacher-student or sempai-kohai martial arts hierarchies, "hai" can sound flippant. (I say CAN, not definitely, and certainly dependent on the disposition of your sempai.)The reason is that many less than disciplined folk say "hai" without thought and without meaning to comply or without gratitude. Well, it isn't uncommon.Slight intonations, if you were to draw out the "hai" as "haaaaai" or use a falling tone, could even make you sound rebellious and cheeky. There is a lot in tonality. And never ever say, "hai, hai", that is like saying "yeah, yeah" (as in "I've heard it all, whatever!")Ossu is an expression from the gut, a primal expression of intent and acceptance and unlikely to be misinterpreted.Just one note, avoid screaming OOOOSSUUUU! so that the paper doors rattle.
If you want to sound elegant and mindful, practice saying ossu at a normal volume. Which would be pitched so your sensei can hear, but not people in the next room. with a little aspiration on the ss sounds (aspiration meaning a slight escape of air). Don't shout the O sound or exaggerate the u sound.This "o" from deep within and the breathiness of the ss imply kokyu, which is breath and suggests pause which implies a moment of respect and enlightenment, and I think that is one of the fundamental appeals of ossu.I took some time to answer you because I thought you asked a good question.Ossu ;)

Thank you, Dave G, for your extensive input. Very much appreciated.
So is this article mainly telling me not to use the word outside the dojo?Our dojo (Shorinji-ryu Renshinkan) doesn't teach the use of "Osu", but there's at least one black belt who does it when bowing to his training partner. I tend to reply accordingly.
I learned the word from another dojo (Kimura-style Shukokai), where we would use "osu" to express gratitude or acknowledgement, rather than "hai".Again, thank you for the linguistics as well. I don't actively study Japanese, but in my understanding, saying "hai" sharply and with an ascending intonation signifies a respectful and brisk attitude.I have kind of imagined the deep 'O' in "osu" to be a bit like the exhaling technique in Goju-ryu's Sanchin breathing.Did I catch your drift right?

I can confirm that "OSS-u" is used in Yoshinkai Aikido here in Toronto, primarily in bowing in and bowing out from seiza, and primarily when Sensei Kimeda is on the mat.
Also, the way of saying it, with a strong "ossss" and then trailing off the breath, is very much how I recall it.Interesting linguistic points, however. I have some basic Japanese, learned from a female teacher, and didn't grasp for some time that there is a "male" Japanese and a "female" Japanese, with subtle differences that, if not understood and used, send odd messages!

Jesse,Thank you for your interesting research, commentary, and deductions, which has shed some light on what is probably the early etymological roots of the term OSU. This is consistent with my own experience as a MA with 40+ years training in traditional and non-traditional styles. And I think I can solve some of the mystery ..... I trained heavily in Martial Arts in NYC and California ever since the late 1960's and I will tell you this, "OSU" was used EXCLUSIVELY in the NYC dojos in the early 70's, from what I could tell. Due to my parents divorce, I got to fly back and forth a bit during those years, and no one that I trained with in California ever used it, ever, but ALL of my friends back in NYC used it back. I was one of the founders of a MA club at my CUNY college back in NYC in '80, and we used it in our club, but NONE of my traditional Japanese Martial Art instructors used it, nor did my traditional Chinese Martial Instructors ever use it. It was strickly a "NYC Street Martial Art" thing... for those of use who weren't getting everything we wanted from our dojos, or didnt have a dojo, we would gather and OSU was our "code word" .... it meant to us simply, "RESPECT" ....it meant that we both acknowledged that the other was a Martial Artist.it was a click "thing" back then....we would use when we would spar each other in alleys and basements ... only those in the "know" of inner-city NYC Martial Art kids would use it, and then it spread to tournaments.... but then when the UFC / MMA exploded, "OSU" took off with it and gained national and international usage... but way back then, in the 70's and 80's, no one but us used it.I always get a kick today when some UFC guy in California uses it today.~OSU~Arthur

Great article, Jesse-san! Thank you! In our Shotokan club in Illinois the OSS word runs rampant with every Sensei....except for one! He once explained to us that this greeting was one to only be used in exceptional cases....cases where you show an indebtedness to the other person to the extent that you would lay down your life. During our bow in and out, there was silence. During class, after any instruction, it was silence or Hai. This Sensei was so influential in our club that his students were recognized by this way... I had the privilege of training this summer in Japan with many accomplished Senseis, including Kagawa Sensei in Tokyo. To my delight, I did not feel the need to say OSS at any time, and did not really hear it all that much. I look forward to being able to visit and train in Okinawa sometime soon. Thanks again for a great article. Luv your stuff. :-)

Jay it certainly can be used as a greeting, as well as an affirmation, among those in that clique.I think you are correct in responding in kind to those who use it as a greeting to you.Frankly I use it with all sorts of people on the telephone, with male and female customer service people, but then again as part of an overall fluency, I don't use it as my primary "yes", but rather when there is a sequence of polite wrapping up statements, as happens, and all the arigatos and other pleasantries have been exchanged, and I want to give the other party the last word, and show appreciation, and respect, and be a little creative, I might give a gently weighted "ossu" to show that this has all been received with gratitude.About the breathing and the Ossu sound, I don't want to theorize but breathing is something that we should be conscious of and you certainly should try to become aware of it and its relationship to movement and speech. So kudos if you are making those kinds of connections.There is a theological concept of Otodama, and the power of sound, which is certainly revered in the martial arts tradition.These days, especially, when speech patterns come off of television programs and cartoons and are mimicked in masse, the art of modulating one's speech has become a lost art in the US, Japan and everywhere else.This subject we are talking about, Ossu, is a part of that larger aesthetic, above all we need to be mindful of not only the words we choose, but how we pitch them, tonality, dynamics, rhythm, and what impression we are making.It's one more facet of the budo spirit, and becomes one more benefit of martial arts training and familiarization with foreign languages.Words and sounds, when you hear them again and again in different contexts, begin to take on a living meaning for better or worse, you develop a personal relationship with each sound.For me Ossu has come to mean the controlled breath of self discipline and moderation, and an affirmative quality, the "ssu" much like the "ssu" in Yessu... ("Yes" by Japanese pronunciation.) so internally I have the sensation of affirming the other person's intentions and efforts, giving a green light so our common purpose can move ahead...

Here's what I think, based on my experience with Yoshinkan Aikido:hai - affirmative, understood - not used any longer in class
osu - respect, understood, agreement, effort, strength; seems better than "hai"
kiai - attacking sound
ichi, ni, san ... - counting the steps of a techniqueI think the meaning and value of "Osu" comes from its sound and connotations rather than any particular origin or derivation. The "O" prefix signifies respect in Japanese, and gives a strong start to the sound, while the "su" suggests strength, effort, and powerful breathing. It is a good general affirmative word for the dojo, when conversation and argument is not be encouraged during class. I don't feel that it is disrespectful at all, quite the opposite it signifies strong agreement and cooperation. There is a martial feel to it, similar to "yes sir", which is fully appropriate in a martial arts class."hai" is a weaker, more controlled and constricted sound, not so suitable for martial arts in my opinion.Kiai is different from "hai", it is a loud attacking shout used to unbalance your opponent and focus your energy.Counting the steps of a technique helps everyone in the dojo to stay in sync. 1. If the dojo is crowded it's important to stay in sync for safety, especially when doing throws. 2. If we don't stay in sync the class will look chaotic, it will be confusing for students the sensei and observers. 3. If we stay in sync, we can sometimes improve our technique by observing other students out of the corner of our eyes!Finally, the very limited set of words allowed will keep students focused on learning rather than conversation. The main class is for everyone to learn from the sensei, not for Q&A, arguments, or general conversation and chat. The sensei can correct your technique without you having to ask a question, and can answer questions after the class. Conversation during class is be distracting.I'm not sure where Bruce Lee's disconcerting sound effects fit in to all this...!

Nice summary, Jesse.I've never seen or heard ossu used by a Japanese either giving or receiving instruction in any Shotokan class, although its very common in general classes in South Africa, where its often pronounced with the same sound as "goose" or 'use" in English.I did once hear Kanazawa sensei say once it after a seminar, (sounded like "hoss") to the whole of our group in attendance, and I got the distinct impression he was being accommodating of our local tendency and going with the flow.I suspect that when Japanese do use it (in Shotokan schools) its a case of when in Rome do as the Romans do.
I recall standing by an elevator in a Tokyo hotel waiting for a buddy, wearing my karate association windbreaker top, when an entire Japanese high school baseball team filed past in the lobby, and each one smiled some tipped their caps and most said "oss." Either taking the mickey, or recognition of some sort.

Thank you for this article. As a Japanese American martial artist, I hear this from time to time, and I've wondered what its meaning is to the martial arts community. If "OSU" has evolved past the traditional Japanese meaning to mean something awesome and good, then that's great. But as a Japanese speaker, I'm always taken aback because it is VERY masculine, bro-some, and slightly douchey.

Same use, but slightly different story:Ive always been told that "osu" is short for yes/understood. That is also how I have noticed it being used across styles and federations ind Denmark, and even by visiting japanese instructors acroos styles. Ive noticed it used similar in Sweden, and by germans as well. When I went to Japan last year, I also noticed that it is sometimes being used by the japanese as well, but usually by the younger, while the more experienced karate-ka's mostly do "hai".After a trip to Japan, we have tried going more the "hai" way in our dojo, but I think its a long way from changeing, especially as the japanese have started using it more, Europeans have a tendency to copy, or adapt to what the japanese do, at least in my experience.

Jesse-san, this is a good article. can provide a more detailed explanation of the question students at school. a lot of karateka even coaches who never explain this, they will only answer follow the course, mentioned osh!

Strange enough what I read here.
Jesse-San thanks for the article and thanks for all comments, but my experience (my first day in a dojo was 1977 and I still train and compete) is that Oss is used as a sign of respect. Actually we say it when bowing at the beginning and at the end, or when Sensei instruct or comment on something.
This is what we have been tought in Italy by our Japanese masters.
So to me and all the people I know is used like "yes sir", "yes master" or the like or as a sign of respect with students or other peer level. Whenever there is Rei to show.
I feel odd thinking I might have misused it for these "few years" both as a student as well as a teacher.
I'm going to ask our Japanese Sensei.
Thanks for bringing it up to my attention, though.

In Sweden, with SKA following JKA, I'm pretty sure everyone uses oss as the go-to response to sensei's instructions, and as greeting when entering and exiting the dojo. I know we all did. Also when greeting the sensei, when bowing after the short sit-down meditation, before class. If I remember correctly, there was either a standing or sitting bow after class too. Embarrassingly, I have to admit that it's been twenty years since I practiced last. However, I know my sensei is still going and our head sensei is too (Ted Hedlund of Enighet in Malmö, Sweden). Those of you who have been around long enough could remember that he came from the US and was one of "founders" of karate in Sweden in the 70s.?

Early in my karate career, in 1973, I studied Chito-Ryu, with a Japanese Sensei. He liked to use Osu, a lot. I migrated in 1983 to Okinawan Shorin-ryu, Shido Kan, with my current Sensei, Seikichi Iha,10th Dan, who is Okinawan. We never use it, but we do use Hai, and onegaishimasu! Sorry we couldn't link up when you were in Canada, Jesse-san. Wishing you well.

Both Suzuki Tatsuo and Shiomitsu Masafumi (both Wado Ryu) specifically asked in seminars that I attended for people to stop saying "Osu". Both said "It is a little rude." When one guy didn't stop in Suzuki Sensei's seminar, it went "very badly" for him.

Nice post except the point of not using it to Japanese, of higher rank, etc..
During my Kyokushin experience in Japan, OSU is 'always' used as a prefix to address a sempai (senior) for any concern from asking questions to addressing personal matters. Usualy in the matter of: Osu, shitsure shimasu (excuse me)... It is always used as acknowledgment after receiving instructions.
Each ryu/school is different but Kyokushin and all the branch out schools are generally like this!
Keep training !

According to Shuji Tasaki Hanshi 9th Dan JKF Goju Kai (deceased) OSS has a very specific meaning. When asked in an interview to explain the meaning of OSS, he responded: "It is an important Japanese Value. OSS means 'Endure and suppress yourself." It should not be used frivolously. Often I ask people if they know what they are saying. It is an abbreviation of Oshi Shinobu."

Cool article!I can tell you that the "Osss..." is still very prevalent in the Japanese Maritime Self-Defense Force ("Navy" would be much easier to say, but it's not a navy due to laws in force today). Ossssu comes flying from all directions as people hurry to and fro in the morning, trying to get into their appointed places on-time, and likely sparing themselves a few syllables in the process. I buy-in to the shortened ohayo gozaimasu theory.So it was interesting to see that mention of the Imperial Navy above as part of the origin. Not sure that "group-think" combined with "militaristic undertones" up top is a very flattering way to describe a common purpose, discipline or unity. Karate is a "martial" art, no? So would karate be a bunch of dudes all group-thinking around? I don't think so.

A girl in our dojo uses "Oss!" for absolutely everything! I think it's alright to say it when our sensei explains something or sometimes outside of our dojo when we attend Karate events. But ... she uses it for EVERYTHING. Not only it gets annoying after some time but now after I read your article Jesse-san, it has a new meaning to me. "Oss!" shouldn't be used careless. Saying "Oss!" just because it sounds "cool" outside of the dojo is wrong to me. For me it sounds very disrespectful the way that girl says it. She uses "Oss!" in situations in which it's not appropriate to say it. I think for her it lost the meaning. Of course, everyone has their own opinions and I respect that. And every dojo learns it different. But pay attention when you talk to Japanese people.By the way, I really love your website Jesse-san. :)

I've been training in Karate since the late 70s and when training with Japanese teachers Osu was the norm, while Hai was used by my Okinawian instructors. I believe it has much to do with distinguishing Japanese karate from Okinawian karate.

In my Dojo where uechi-ryu and shito-ryu is teached, I never have heard "Oss" we always have used to start any activity with a partner or enter in the dojo "Yoroshiku Onegaishimasu" and to finish the activity or to leave the dojo "domo arigato gozaimashita". And to reply to the sensei "Hai sensesi".

Hello,
In brazil, at least in traditional Karate, we use osu as a demonstration Of respect, in the beginning and end Of the training. It's also used To agree with a "order" or solicitation Of our Sensei, And To greet colleagues When we Get in the Dojo. I don't see people using as a "whats up" or outside the dojo. Sometimes we use Hai To agree Too, or other sound, but this sound sometimes isn't knowing for human ears!!!
In brazil we have two japanese shihans, now i'm embarassing about saying osu to them! Omg!

It's been more than three years that I've been living in Japan and I've trained in Full-Contact Karate only (Byakuren, Ashihara and Kyokushin).
I don't know much about the origin of the word but in this kind of environment it is used in almost all the situations listed at the beginning of the article; more specifically I'll reduce them to: “hi”, “hello”, “goodbye”, “okay”, “thanks”, “I understand”.
Senseis use it ONLY for greeting students at the beginning and end of the class. Students use it for greeting and any time they must thank or show understanding; basically anytime the Sensei ends a phrase!

So women can't display "strong assertiveness, masculinity and “let’s-kick-butt” spirit"?I obviously understand the importance of tradition, however excluding someone because of their gender is something that should surely be left behind in the early 20th century where the term originated.If the boy next to me is using the term and meaning it then I sure as hell am going to too.

Phil Redmond wrote an excellent article on this subject years ago on his sadly missed 24fightingchickens web site and was widely vilified for saying exactly what Jesse has just repeated.It's good to see the next generation pointing out the silliness of this word, which is incorrectly used as the swiss army knife of dojo vocabulary.I wouldn't mind if its adherents did not look down on those who decline to use it, as I always have.

Greetings Jesse!Thank you for helping to clear up the "oss-anomoly". I feel that it's important that we pay attention to the cultural aspects involving the use of both foreign grammar (however informal) and its corresponding social etiquette. I'm also glad that you provided more appropriate alternatives to the word, ones more widely accepted used. Great work, here Jesse --- I'll be sure to pass on the info!

Entertaining and informative article, Jesse! I am a taekwondoist, so I've never used the "osu." My brother, however, became a kajukenfu kenpo practitioner many years ago, and everyone in his school uses "osu" all the time. I keep in touch with many of them through their Facebook page, and it's like Old MacDonald: here an "osu," there an "osu," everywhere an "osu, osu." lol In fact, my curiosity as to why they use it so often led me to google the term, which led me to your article. Small world! Anyway, I thought I'd add my two cents to this discussion, which apparently has been going on for a few years since you published this thing. The first time I even heard the word "osu" used was in a Sonny Chiba movie, "Champion of Death." My brother and I were teenagers at the time, and saw it in an Army base theater in 1979. Chiba's character demanded that his students yell "osu" as their kiai, and he would beat them if they yelled anything else. It was kind of comical. Do you think Chiba's movies had any influence in the proliferation of the "osu" in Western karate culture?

In my dojo we use it for two things. Students use it to affirm that they understand, and at the beginning and/or end of a spar/fight (in dojo). High ranking black belts use it to enter or exit the dojo. Every one else says 'Courtesy' to come in or out.

Osu is as common in almost every non-Asian dojo as is the use of weird things done in Korean arts: tang soo in Tang Soo Do, hapki, kuk sool, kong shin (and that one actually does work) and many more. Why yell "China Hand", Co-ordinated Power, National Technique, Empty Mind, etc. The instructors seem to think the use makes them, I guess, sound like the have jung shin but, to those who know the meanings of the words, they actually sound foolish. I know I hate yelling "kong shin" 3-4 times while bowing in to a class or at seminars and such.

I was invited to work with a dojo where it was oss every entry to the dojo and response to the Sensei and at least twenty times a class. It seemed like it was more of a power trip for the Sensei-owner than anything else. Any time I was teaching I did not expect the oss response and the owner got all up in the kids faces and tossing out push ups and stuff. His way of discipline I suppose. Some of the students had been working with this guy for three years and still could not perform their first three forms with any confidence but could say oss just fine. It just seemed that the oss thing was so over done that it didnt mean anything. About as traditional as fortune cookies.

I've always found this an interesting topic. I remember living and training in Japan when saying "Oss" became a thing in the west.Initially, I found it strange because no one really knew what are why they were saying it (outside of Japan).But as it gained popularity, even Japan embraced it, making OSS shirts, etc.Ultimately, I think it's a mixture of all three reasons mentioned in the article. Arriving at the gym in the morning before training, we always greeted each other with Ohayou Goazaimasu, or Oss.When training got difficult, many would push through the pain, say Oss and continue fighting.When training away from your main gym and entering a new dojo, one would often say Onegaishimasu to greet everyone. This too gradually becomes Oss overtime.Nowadays, I think many Japanese have embraced it because of its popularity in the west (which is a bit odd) but, also makes it acceptable in most settings, especially with men.

Dear Jesse-Sensei,
I just wanted to say thanks for this article. I can't count how many times I've referred people to it, shared it and otherwise used it to educate. Iv'e studied Japanese Budo for about 11 years now direct, and westernised jujutsu before that, and, it's driven me slightly nuts that students follow the herd behaviour and don't observe the Japanese practitioners of Budo and their actual manners, and seem to know nothing of rei-ho.
So a big "arigato gozaimashita" from me, please keep writing your excellent and very helpful blog.

I have to agree with the people who have said "but what about when the Japanese Instructors themselves use it ?" I agree with you Jesse about it in everyday conversation with people you don't know, but when it comes to the dojo or each other, why not follow the traditions of our most senior instructors. On this webpage http://www.skifworld.com/skif-ascension.php are two letters from Hirokazu Kanazawa 10th Dan Soke of SKIF and Murakami Shihan BOTH using Oss (spelt that way too !) as the closing greeting.

When I began my karate training my first day was learning to bow correctly, and respectfully. My sensei told us that the proper bow is done with a little bit of aspiration, or outward breath. It is not intended to be made heard, but simply to allow good air flow through the body. However it is not unusual to hear someone breathe and if after a good training session, it is expected. He never went into the details of Japanese etiquette, but simply told us that there is no word there, just a breath. This prompts me to wonder if maybe people hearing the aspiration, or outward breath mistook the sound as a vocalization. I realize that my explanation is possibly off the wall, but neither I nor my brother and sister karateka ever said oss or osu. But actually took up the habit of sounding the breath during a bow.

The term "osu" in the dojo where I train in England is only used when entering and exiting, as a sign that you will persevere and endure during training, and that you have persevered and endured after. A form of pledging your whole self to the training, and acknowledging that you have trained to the best of your ability, and that you have pushed yourself.

Good Article. The main point that I'm seeing here is not the use of the word, but rather the miss-use of the word. We use both in my dojo (Osu & Hai). I'm very careful to point out to my students, when it is and isn't proper to use them. Dr. Tesshin Hamada (Hanshi and current President of the Dai Nippon Butoku Kai) teaches that Osu means to "press-on" (similar to the Kyokushin meaning). I also read an interview with the late Shuji Tasaki (Founder of the Seiwakai Gojuryu organization and said to be the #1 student of Gogen Yamaguchi), who also defined "Osu" as meaning to "press-on". I have been to dojo's in Japan where it is used, and some where it isn't used (Just like the US). I think the important thing is to use it only when proper and to avoid its miss-use.Respectfully,Dan Taylor
Visalia, CA

In a Portuguese Karate Shotokan Dojo, our 3th Dan Master had been to japan several times, mainly for learning and we used OSU only when first stepping up in the tatami, and always facing him with a slight bow as in casual japanese greetings. Appart from there there were no estrangeirisms besides the names of punchs and kicks depending on heights if I remember properly and maybe some katas. In general it involved the apprentice's interest for him to talk about that otherwise he would give us general directions for 1/3 of the class and sometimes we did some choral Kiai during those. the other 2/3 of class were divided in body heating and decompressing and individual time with the master by belt rank. That being said the second and last OSU of the day would be exaclty the same but when leaving. In my opinion I think it's rather a greeting system then a punchline for keeping students alert. I also find interesting to see the japanese abreviation theories and I think they are very likely truth as that often occurs in japanese language specially with greetings.

I guess it really depends. I'd never use the word if I was with someone of higher rank. I'm also a woman so it's a big no no, but I'd do it if I'm with a group and everyone says it or if my instructor wants us to say it. In Kyokushin, it symbolizes the fighting spirit, respect and comprehension of requests.

Hi Jesse, I am a Wado Ryu practitioner and a member of the Wado Ryu Renmei and Wado Ryu academy. These organisations a steeped in Japanese tradition and Osu is never used and frowned on if used. They regard it as a non Japanes term, it does not exist in Japanese. They believe that it may have originated after WWII with the American occupation and the participation of the Americans in the Japanese martial arts.
If you want my theory, it may have been the phrase Ah so. Quite often Japanese when they agree or understand something they say Ah So or So said several times such as so so so. The Americans may have converted So So to osu

Thank you for providing the history and theories behind the use of Osu. As a Shotokan practitioner, we definitely fall into the Osu category. The only comment I would like to offer is that ultimately, while a cultural context lesson is always valuable, the most important consideration for the Karateka is knowing the context of the expression's use in your dojo. If you are usining it because it has been defined as an expression of respect, to acknowledge understanding and attention to the instructor, then this is the most important thing. Our world is full of examples where we get things a little wrong, but if the goal is to foster character development, focus and mutual respect and decorum, then I would suggest that historical appropriation is a minor and forgivable matter. Good discussion!

Can I just congratulate everyone for being the most polite set of comments I have ever seen on the Internet. I didn't check 100% but they all seemed extremely respectful. This is why I attend and take my children to Karate - respect, honour, confidence, fitness and self defense. Thank you for the post. Each of you are what makes this world great when this modern world seems so intent on destroying itself. Here in the UK this level of respect and honour seems very rare outside of a dojo. You all have my kindest regards and best wishes.

Well yeah sometimes I use "OSS/OSU" in our Class or Dojo but I'm not Japanese or what. Its just that my friend in Japan often greet us with "OSS/OSU" and I got it from him.
P.S. I'm not Karate Martial Artist. I'am Taekwondo and MMA.

I use osu in my training because it's demanded in my category(kyokushin)It also slips out of off my mouth in public places because I use it so much in training. Can't really help it.But never use it on purpose in the wrong place or to the wrong people. Have great respect for the Japanese language and the correct use of it.

With all due respect, this article does not give the complete answer on the word "Osu!". Sadly though, reading the comments, it seems like people take it as just that: "Finally I get it, now I'll explain this to my sensei", or "we won't use it around women" and so on.Jesse, you say that it doesn't really matter where it derives from - but as a person who's spent a lot of time in Japan, shouldn't you know that context is everything? It's like discussing whether "kami" means god or hair, until a third person comes along and says it means paper. They're all correct, aren't they? We have the same in all languages I suppose: A crane can be both a bird and a machine used to lift heavy objects. And this is important:I am familiar with "osu" as a slang word for "hi". Whether it derived from "ohayou gozaimasu" or not I don't know, but it's quite commonly used among young guys in Japan. This word is as you say not considered polite, and quite masculine. Therefore, as you mention as well, not used as much by women.Then you have the "osu" from kyokushin karate, partly also adapted into other styles. This has nothing to do with slang, and has the military undertone (and background). In kyokushin dojos (and probably other dojos as well, but here I would be on unsteady grounds) in Japan, the term is used consistently. It is about showing respect, obedience and will to fight/give all. Although women in kyokushin karate have also had to fight for their rights in a male dominated sport/art, in this context "osu" is used -equally- between genders,As a kyokushin practitioner, I will use "osu!" in Japan. But again, it's all about context: I will never say it to a non-karateka, as it will both be out of place and there's the issue of context - am I using rude slang, or am I in the karate mindset? No way to tell. I will use it when I great my fellow karateka, and they greet me the same way. I will use it in training, as this is the kyokushin way.I realize frustration will arise from the overuse of "osu", used with no understanding of it's origins. It is not a "kiai", it is not a fill word to be used the way some teenagers use "like" four times in a sentence. But we also need to acknowledge the importance of "osu" in the right settings, and neglecting to differentiate between osu as slang as and osu in kyokushin karate is just as grave an error.If a dojo decides to adopt the word "osu", what is the harm? Don't fret over such details, ask whether they teach the important core values of traditional martial arts; ask whether the sensei is competent in their field. Because really - who gets to decide who owns the "osu"?

Thanks for the great article. I had no idea that it was considered bad form to use, "ous" as a woman. I used it all the time to men, women and those of higher ranks. I remember saying to Master Yaguchi during our annual class with him when he'd visit. No one ever told me it was considered bad form. Though I remember using, "hai" in his presence, I clearly remember saying "ous" along with the rest of my classmates.

I'm doing Okinawan kobudo, so we say "hai!" A lot. And sometimes, when we start a drill or some kumite, I never know if my partner says "hai!" Like "let's go/start!" Or "hi!" to greet me. But I can reply with a "Hai!/Hi!" To both of them, so it's not something too bad

I currently live in Japan and joined BJJ where I hear the term Osu more than anything. After my first week at BJJ I began asking friends at school about its meaning and for the most part I got a bunch of confused faces or explanation of how only men use it. Regardless, I've found myself in various situations now where it seems expected of me to say. Usually when entering the Dojo, sparring, entering the locker room, or simply greeting people at the dojo. Since I am new I am of course of lowest rank. Further, I am very young compared to everyone else at my dojo. My intent is not to be offensive by misusing the word. Especially since it is of course, Japan. Any advice?

I read it a lot on FB. Interesting article. I have said osu to Asano, Enoeda, Kawasoe and Kanazawa Sensei and probably a whole lot more in my dim and distant past. I do remember the when passing Sensei Asano in a hall way we had to stop, bow our heads and say osu. I also remember him walking up to me during a leg stretch (the one where you stand on one leg and your partner pushes the other one towards your face) he pushed my leg until my toes touched the wall behind me, laughed and said now is stretched, osu! I tried not to show any reaction or flinch with pain, as the fibers of my hamstring screamed, and replied with a strong osu and a smile to acknowledge his somewhat devilish sense of humour. I took his nod as a sign of approval.
Oh for the good old days, sadly I suffer with the damage from 6 classes a week and a return seems nothing short of a miracle. Or new hips, knees and back surgery failing said miracle!

This is very interesting to me. My father put me into Aikido (my apologies if my spelling is wrong) when I was very young. He would have my siblings and I kneel when he came home, bow to him and say, "Osu". We only knew we were told to say it but we're never told what it meant. I've suspected it was used incorrectly but until I found your page, I've never known its true origin so I thank you.

Just because I found this post randomly searching for something else and found it amusing, I just wanted to say that while it may not be Okinawan, all the things being called out in both the post and the comments are most definitely a staple of Japanese karate-ka. I have lived in a middle of nowhere little town in Kanto for 3 years, and studied Goju-ryu karate at the local gym along with many of my elementary school students and from our aged black-robed sensei who has 2 missing fingers. When we walk into the dojo, we bow and say "Osu!" When we greet our sensei on arrival (ours or his) we say "Osu!" When we greet each other the first time we say "Osu!" When we bow to start the class: "Osu!" When responding to an instruction: "Osu!" When confirming that we understood what was just instructed: "Osu?!" Our confirmation: "Osu!" When doing drills: Ichi - HAI! Ni - HAI! San - HAI! Shi - HAI! ... Kyu - HAI! Ju - OSU!" That said, the "hai" is actually supposed to be a ki-ai, I was once told by the sensei's second. Anyway, thought you might like to hear the perspective of someone who's studied karate in Japan that wasn't Shotokan or Kyokushin and is far away from Okinawa. I'm just basically explaining that maybe the reason for the proliferation of Osu isn't just a Western thing. ;)

Love this article, not in the last place because of the reactions!In Kyokushin OSU means almost anything from theory #1, but also used as a greeting (#2) and showing respect to the other person (#3). In Kyokushin when you say OSU there are 4 things involved: at the baseline there is the perseverance in your action, then towards the other person there are 2 things you want to say, which are gratitude and respect, and last but surely not least: humility as we are a small part of the Whole or Universum. Perseverance needs a little explanation, since it could be easily interpreted as "pushing one's will" which is an egoistic action. That is NOT the case here. The best interpretation of the word perseverance is - as far as I know - from Margaret Wheatley: https://www.youtube.com/watch?v=LpRPaBGtoZU

Thanks for the article. I currently train Practical Wing Chun, but have done other things in the past and still love exchanging techniques with other styles. In several clubs and also online I find now more and more people saying OSU. Exactly like you described, it is used for everything. I felt for me like "Hey, I am cool, I say OSU (but don't know what it means)." Being blessed with a dark German humour, I replied with "Gesundheit" ;)
Jokes aside, no one was able to tell me anything about it, your article was a great help!

Lived in Japan for 5 years and I can tell you that an American saying "OSS" (or osu for those who think they should nit pick) will never offend any worthy person in Japan. Japanese people are just happy to interact with Americans period, especially in a dojo.

Nice article.Funny story - I'm a Kyokushin student, "Osu" to me is pretty much a statement of enthusiasm rather than an actual word, makes for a decent enough greeting between classmates and an enthusiastic, respectful greeting to Kyokushin seniors.
One of my classmates is Japanese and when I signed up for an open full-contact karate/kickboxing tournament organised by a Japanese born Shotokan instructor he points out that "Osu" is a bit of a disrespectful term to older Japanese folks and I shouldn't use it, just nod, agree and bow like the others did.
So that's what I did.
Tournament organiser was looking forwards to having non-Shotokan practitioners in the mix and apparently I was the only one who'd picked up the gauntlet so he'd looked me up and knew I was a Kyokushin guy and knew about our love of responding to things with an enthusiastic "OSU!" he actually thought my silence meant I was unimpressed and snobbing everybody.
Thanfully he pointed this out a few matches in, found out the story, proverbially laughed his ass off which I'm told is unusual for an older Japanese gentleman so I'm guessing my classmate had an uber-polite upbringing or the TO had spent most of his life in Australia where all this took place and I spent the rest of the tournament being my normal self as a Kyokushin student.Just goes to show context is everything.

As a dojo that is based in Okinawan karate, we use the term Hai but not exclusively. I think it is important for students to use contextual language when making the appropriate response.As I understand it, some such responses such as "oss" depending upon the instructor, can be considered braggadocios and lacking of humility. In others it can simply be a symbol of perseverance.Personally we use a variety of phrases for different things.Upon entering the dojo we often will use a customary greeting such as Konban wa! Such is just polite conversation.On the floor, when we bow in we say "dozo onegaishimasu". This is to demonstrate a position of humility and a readiness to learn from one another. It could be attributed to saying, "please teach me" or "I am ready to learn".When asked a question or to do something "Hai" is an affirmative answer or a way of politely acknowledging that you heard or understood what was asked/said by sensei.Other times a student may say "arigato" if they ask a question and it is answered or they ask permission to do something.Teaching cross culturally is important because I think Jesse points out that cultural viewpoints do not always translate with languages.I think the best advice is to try to first adhere to what is normal and acceptable widespread cultural practice first, acceptable dojo etiquette second and lastly what is considered "familiar" language among peers last (as in between good friends).For my personal dojo, I try to emphasize on observing the cultural norms of what is considered polite, respectful and friendly. I do this personally because I think it promotes a behavior type that is synonymous with the language expression.

We use OSS in BJJ and is used with utmost respect... and perhaps it has been appropriated incorrectly as described in this article but language itself evolves with culture and this is what has happened in martial arts. You can’t solidify a language or words like this. The classic example is the work “gay” meaning happy now means, well gay. For some reason I know that teenage girls actually lead the language changes so get ready for “like” to start every sentence!!! Like, you know what I mean?Thanks for the tip though on Japanese culture, I’ll make sure I don’t use it in contexts that it isn’t respectful or appropriate.